Round the bend

The paper reported a study whose objective was “To find out whether taking images of the male and female genitals during coitus is feasible and . . . whether former and current ideas about the anatomy during sexual intercourse and during female sexual arousal are based on assumptions or on facts.”1

The main findings, based on 13 experiments performed with eight couples and three single women, were that during intercourse in the “missionary position” the penis assumes the shape of a boomerang, and that during sexual arousal the size of the uterus does not increase (as Masters and Johnson23 had believed). The article was accompanied by Leonardo da Vinci’s The Copulation (circa 1493) (fig 1) and RL Dickinson’s midsagittal drawing of the same subject (1933) (fig 2). The “objective” and “true to nature” magnetic resonance images (MRIs) obtained in the 1999 study contradicted the beliefs inscribed in these illustrations.